An experimental study of the merging probability of double buoyancy-controlled jet flame

This article presents an experimental investigation on the merging probability of buoyancy-controlled jet flames. Two rectangular jet nozzles with different aspect ratios and heat release rates were studied in the open space. The nozzles of the same area with dimensions of 1.5 × 24, 3 × 12, and 6 × 6 mm were used in this article. It is found that the merging probability increases with the heat release rate and decreases with the space between these two nozzles. A model to predict the merging probability has been developed, which is proportional to a dimensionless parameter linearly within a certain scope.     

Number of revolutions of a particle around a black hole: Is it infinite or finite?

We consider a particle falling into a rotating black hole. Such a particle makes an infinite number of revolutions n from the viewpoint of a remote observer who uses the Boyer–Lindquist type of coordinates. We examine the behavior of n when it is measured with respect to a local reference frame that also rotates due to dragging effect of spacetime. The crucial point consists here in the observation that for a nonextremal black hole, the leading contributions to n from a particle itself and the reference frame have the same form being in fact universal, so that divergences mutually cancel. As a result, the relative number of revolutions turns out to be finite. For the extremal black hole this is not so, n can be infinite. Different choices of the local reference frame are considered, the results turn out to be the same qualitatively. For illustration, we discuss two explicit examples—rotation in the flat spacetime and in the Kerr metric.     

Boosted cylindrical magnetized Kaluza–Klein wormhole

In this work, we consider a vacuum solution of Kaluza–Klein theory with cylindrical symmetry. We investigate the physical properties of the solution as viewed in four dimensional spacetime, which turns out to be a stationary, cylindrical wormhole supported by a scalar field and a magnetic field oriented along the wormhole. We then apply a boost to the five dimensional solution along the extra dimension, and perform the Kaluza–Klein reduction. As a result, we show that the new solution is still a wormhole with a radial electric field and a magnetic field stretched along the wormhole throat.     

Neutrino-less double beta decay experiments

The observation of neutrinoless double beta decay would unambiguosly demonstrate that neutrinos are Majorana particles and would provide unique information about the ordering and absolute scale of neutrino masses. This very rare decay is actively searched for in a number of candidate isotopes. It violates lepton-number and is predicted by many extensions of the standard model. The most recent experimental results are reviewed. The technological advances and the most compelling requirements for the new generation of experiments are discussed.     

Designing Nanoscale Counter Using Reversible Gate Based on Quantum-Dot Cellular Automata

Some new technologies such as Quantum-dot Cellular Automata (QCA) is suggested to solve the physical limits of the Complementary Metal-Oxide Semiconductor (CMOS) technology. The QCA as one of the novel technologies at nanoscale has potential applications in future computers. This technology has some advantages such as minimal size, high speed, low latency, and low power consumption. As a result, it is used for creating all varieties of memory. Counter circuits as one of the important circuits in the digital systems are composed of some latches, which are connected to each other in series and actually they count input pulses in the circuit. On the other hand, the reversible computations are very important because of their ability in reducing energy in nanometer circuits. Improving the energy efficiency, increasing the speed of nanometer circuits, increasing the portability of system, making smaller components of the circuit in a nuclear size and reducing the power consumption are considered as the usage of reversible logic. Therefore, this paper aims to design a two-bit reversible counter that is optimized on the basis of QCA using an improved reversible gate. The proposed reversible structure of 2-bit counter can be increased to 3-bit, 4-bit and more. The advantages of the proposed design have been shown using QCADesigner in terms of the delay in comparison with previous circuits.     

Förster Resonance Energy Transfer Study of Cytochrome <Emphasis Type="Italic">c</Emphasis>—Lipid Interactions

Specific interactions between a mitochondrial hemoprotein cytochrome c (cyt c) and cardiolipin, a lipid component of mitochondrial membrane, are crucial to electron shuttling and apoptotic activities of this protein. In the present study the Förster resonance energy transfer (FRET) between anthrylvinyl-labeled phosphatidylcholine as a donor and heme moiety of cyt c as an acceptor was employed to give a quantitative characterization of the protein binding to the model membranes from the mixtures of phosphatidylcholine (PC) with phosphatidylglycerol (PG), phosphatidylserine (PS) or cardiolipin (CL) in different molar ratios. The multiple arrays of the FRET data were globally analyzed in terms of the model of energy transfer in two-dimensional systems combined with the scaled particle adsorption model. The arguments in favor of the specificity of cyt c interactions with CL were obtained, including the higher adsorption potential and the deeper protein insertion in the lipid bilayer.     

Photophysical and Electrochemical Studies of 4-Dicyanomethylene 2,6-Dimethyl-4H-Pyran (DDP) Dye with Amides in Water

Photophysical and electrochemical studies of DDP dye with Formamide and alkyl substituted amides were carried out in water. Addition of Formamide (F), Acetamide (ACM), N,N-Dimethylformamide (DMF), Dimethylacetamide (DMAC) to DDP dye result in an isosbestic point. A fluorescence enhancement of DDP dye is observed on the addition of amides. Apart from the fluorescence enhancement, the addition of formamide result in no significant shift in the position of emission maxima of DDP dye whereas addition of ACM and DMF result in a shift towards the blue and red region respectively. DDP dye exhibits three lifetime components which are unique in lifetime and amplitude. The fluorescence lifetime and relative amplitude of DDP dye varies significantly by addition of amides in aqueous solution which are influenced by amidewater hydrogen-bonding network and hydrophobic influences of the alkyl substituted amides. The nature of interaction between dye and amide be predominantly through hydrogen-bonding wherein the carbonyl oxygen (C=O) of amides are bonded to N-H hydrogen of DDP dye through water molecule. The existence of more than one microenvironment of DDP dye in aqueous phase is elucidated by Electrochemical Impedence Spectroscopy (EIS) through Nyquist plots wherein it signifies that there exist at least three different micro environments which support the existence of different fluorescence lifetimes. Fluorescence spectral technique is used as an efficient tool to elucidate the nature of interaction of water soluble probe with hydrogen-bonding solutes is established in our studies.